The present invention relates to an automatic pipe inspection system for inspecting the acceptability of the inner diameter and bending of pipes of the type in which a cylindrical gage is inserted into one end of a pipe to be inspected and forced to pass therethrough to the other end thereof under the driving force of the fluid under pressure so that the pipe through which the gage has passed is passed through inspection while the pipe through which the gage cannot pass is rejected with the gage stopped therein.
In one of the conventional methods for inspecting the acceptability of the inner diameter and bending of pipes, a rope or the like having one end attached to a gage is manually inserted through a pipe to be inspected from one end thereof and is pulled out of the other end of the pipe to pass the gage therethrough. With the increase in length of recently manufactured pipes, the wire having a length longer than that of a pipe to be inspected must be prepared, and consequently it takes a relatively long time for an inspector to insert the wire through the pipe so that the quick pipe inspection cannot be accomplished.
In another conventional method, a rod with a gage attached to one end thereof is driven mechanically to pass through a pipe to be inspected. Therefore the rod again must be longer in length than a pipe to be inspected, and the rod must be inserted into the pipe from one end thereof, pulled out of the other end and then returned to the initial position. In addition, a relatively large pipe inspection area is required because of a relatively large space required for installation of the device for supporting a pipe to be inspected and driving the rod with the gage through the pipe.
In a further conventional method, a gage is inserted into the pipe to be inspected from one end thereof, and then an air gun is inserted into one end of the pipe to admit the air under pressure behind the gage in the pipe, thereby forcing the gage through the pipe toward the other end thereof. However to carry out this inspection method, skilled laborers are required because only they can safely handle the portable air gun to fire the gage through the pipe. This operation is apparently too dangerous for unskilled laborers. In addition, they must precisely locate the gage and the air gun in inspection position which is different for each pipe to be inspected. Furthermore, this method requires an additional laborer who stands at the other end of a pipe to be inspected to place a stopper at the other end of the pipe so that the gage may be prevented from being shot out of the pipe. This laborer must change his position depending upon the length of a pipe to be inspected. Moreover his operation must be precisely synchronized with the operation of the air gun operator so that the gage shot out of the pipe will never hit him and any other equipment therearound. When the gage strikes against an object, it will be inevitably deformed or damaged and cannot be used for further inspections. Even though the above pipe inspection method for firing the gage through a pipe to be inspected is mechanized to some extent, it still requires manual operations. Therefore the pipe inspection is considerably dependent upon the experience and skill of the inspectors, and consequently the inspection efficiency in terms of the number of pipes inspected per man is relatively low. Furthermore, the above method cannot provide a fully safeguarded pipe inspection so that the inspectors and equipment therearound will have no fear that they may be hit by the flying gage.
In view of the above, one of the objects of the present invention is to eliminate the above and other problems encountered in the conventional pipe inspection methods and devices.
Another object of the present invention is to provide a fully mechanized or automated pipe inspection device which may accomplish the rapid pipe inspection, thus increasing the pipe inspection efficiency in terms of the number of pipes inspected per man, may ensure a fully safeguarded operation even by unskilled laborers eliminating the accident of the gage being shot out of the pipe and hitting the inspectors and equipment, may attain economy of laborers and may minimize the damage to the gage, thereby ensuring a long service life thereof.
The pipes to be inspected vary in diameter and length over a wide range. Therefore a pipe inspection device must accomplish a rapid yet fully safeguarded inspection regardless of the experience and the degree of skill of the laborers.
A further object of the present invention is therefore to provide a pipe inspection device which may accomplish a rapid and reliable pipe inspection regardless of the change in diameter and length of pipes to be inspected, that is, the pipe inspection device being suitably adjusted within a short time depending upon the size of a pipe to be inspected, whereby the pipe inspection efficiency may be remarkably improved.
A further object of the present invention is to provide an improved automatic pipe inspection device in which a gage which is discharged out of the other end of a pipe may be automatically and quickly returned to the firing position for the next inspection so as to be automatically inserted into the next pipe to be inspected.